In traditional Catholic sacramental theology, four things are necessary to have a valid and fruitful Confession: contrition, confession, absolution, and satisfaction. Too often we tend to minimize the importance of contrition, taking it to simply mean a momentary sorrow or regret. It certainly is a kind of regret, but not merely momentary, for contrition also necessitates the firm desire not to commit that particular sin again. Of course, though through human weakness our resolutions often fail us, they are still essential. An act of contrition for a particular sin requires the sincere desire to avoid committing that sin in the future.
This means obviously that true sorrow for sin is incompatible with the intentional to continue committing it. One cannot simultaneously repent of sin and receive absolution while lacking any will to cease committing the offense. One cannot be absolved from a state of sin while continuing to persist in that sinful state.
"When anyone has really given up his sins, he must not be content simply with bewailing them. He must also give up, leave far behind, and fly from anything which is capable of leading him in the direction of them again. In other words, my dear brethren, we must be ready to suffer anything rather than fall back into those sins which we have just confessed. People should be able to see a complete change in us; otherwise we have not merited Absolution, and it could even be possible that we have indeed committed sacrilege.
Alas, that there are few in whom this change is apparent after having received Absolution! Dear God, what sacrileges are committed! If in every thirty Absolutions there were but one genuine case, how soon would the world be converted!
Those people do not merit Absolution, then, who do not give sufficient signs of contrition. Alas, how many times, because they are sent away, do they not come back anymore! This, of course, is because they have no real urge to be converted, for if they truly had, very far from leaving their Confession until another Easter, they would be working with all their hearts to change their lives and return to make their peace with God." 
I will not offer any further commentary upon the point, but those with ears to hear can easily see its relevance to our contemporary situation.
 Sermons of the Curé of Ars, trans. Una Morrissey (TAN Books: Rockford, Ill, 1995), pp. 125-126